Bohm, J.
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An Experimental Study of the a-Dependence of $J/\psi$ Photoproduction

The Fermilab Tagged Photon Spectrometer collaboration Sokoloff, M.D. ; dos Anjos, J.C.C. ; Appel, J.A. ; et al.
Phys.Rev.Lett. 57 (1986) 3003, 1986.
Inspire Record 235061 DOI 10.17182/hepdata.20205

We have studied the photoproduction of Jψ mesons on H, Be, Fe, and Pb targets using real photons at a mean energy of 120 GeV. The pT2 spectra were used to separate the coherent diffractive signals from the incoherent signals. Parametrizing the per-nucleus cross sections in terms of power-law dependences, Aα, we find that αcoh=1.40±0.06±0.04 for the coherent diffractive signals and αincoh=0.94±0.02±0.03 for the incoherent signals.

1 data table
Table 1

CROSS-SECTIONS ARE RELATIVE TO THAT FOR INCOHERENT J/PSI PRODUCTION OFF BERYLLIUM.


rivet Analysis
Observation of Tensor and Scalar Mesons Produced in $e^+ e^-$ Annihilation at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Rev.Lett. 57 (1986) 1990, 1986.
Inspire Record 18688 DOI 10.17182/hepdata.20227

The production of the tensor mesons f0(1270) and K*0(1430) and the scalar meson S(975) has been observed in e+e− annihilation at 29 GeV center-of-mass energy by use of data obtained with the high-resolution spectrometer at the SLAC e+e− storage ring PEP. The mean multiplicities for meson momenta greater than 1450 MeV/c are 〈nf0〉=0.11±0.04, 〈nK*0(1430)〉=0.10±0.06, and 〈nS〉=0.05±0.02 per hadronic event. The fragmentation functions of the tensor mesons are in good agreement with the predictions of the Webber cluster model. The data are consistent with a predominant strange-quark content on the S meson.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Measurement of the Branching Ratio for $\Upsilon^\prime$-prime $\to \mu \mu$

Kaarsberg, T. ; Lee-Franzini, Juliet ; Lovelock, D.M.J. ; et al.
Phys.Rev.D 35 (1987) 2265, 1987.
Inspire Record 230842 DOI 10.17182/hepdata.23382

Using the CUSB-II detector at the Cornell Electron Storage Ring, we have measured Bμμ, the branching fraction into muons, of the Υ’’ meson. We find Bμμ(Υ’’)=(1.53±0.33±0.21)%, from which the Υ’’ total decay width is 25.5±5.0 keV. From this result we obtain αs=0.170−0.012+0.015, ΛMS¯=148−39+56 MeV. (MS¯ denotes the modified minimal-subtraction scheme).

1 data table
Table 1

No description provided.


rivet Analysis
A Study of the Decay $B \to \psi$ X

The CLEO collaboration Alam, M.S. ; Katayama, N. ; Kim, I.J. ; et al.
Phys.Rev.D 34 (1986) 3279, 1986.
Inspire Record 230961 DOI 10.17182/hepdata.23447

We have measured the inclusive branching ratio for B→ψX to be (1.09±0.16±0.21)%, and the exclusive branching ratios for B−→ψK− and B¯ ¯0 *0 to be (0.09±0.05)% and (0.41±0.18)%, respectively. The mass difference between neutral and charged B mesons is 1.1±2.1 MeV, while the difference between the mass of Υ(4S) and twice the mean B-meson mass is 18.5±3.0 MeV. The ψ momentum distribution implies a substantial two-body decay (in agreement with direct measurements), but also some combination of B→ψX with MX>1.5 GeV, and B→ψ’X.

2 data tables
Table 1

No error for cross-section given in text.

Table 2

No description provided.


Diffraction Dissociation at the {CERN} Pulsed Collider at {CM} Energies of 900-{GeV} and 200-{GeV}

The UA5 collaboration Ansorge, R.E. ; Åsman, B. ; Booth, C.N. ; et al.
Z.Phys.C 33 (1986) 175, 1986.
Inspire Record 232615 DOI 10.17182/hepdata.15812

Cross-sections for diffractive particle production and pseudorapidity distributions of the decay products of diffractive states are presented. The data were obtained with the UA 5 streamer chamber detector at the CERNpp Collider operated in a new pulsed mode yieldingpp interactions at c.m. energies of 900 and 200 GeV. Data recorded with a special trigger designed to select a sample of events enriched in single-diffractive interactions clearly favour apt-limited fragmentation of diffractive states. The cross-section for single-diffractive particle production ϊ was found to be 7.8±0.5±1.1 mb at 900 GeV and 4.8±0.5±0.8 mb at 200 GeV (first error statistical, second systematic). From the pseudorapidity distribution of diffractive states we deduce the average number of charged particles to be 6.5±1.0 at 900 GeV and 4.1±1.1 at 200 GeV. Furthermore we report on our estimates for the cross-section of double-diffractive particle production at both Collider energies.

3 data tables
Table 1

Single diffractive cross sections.

Table 2

Average number of single diffractive charged particles.

Table 3

Estimate of the double diffractive cross sections.


$\rho^0$ and $\omega$ Production in Deep Inelastic $\mu p$ Interactions at 280-{GeV}/$c$

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Z.Phys.C 33 (1986) 167, 1986.
Inspire Record 231103 DOI 10.17182/hepdata.15815

Inclusive distributions of ρ0 and ω mesons have been measured in deep inelastic μ-p interactions at 280 GeV/c. A comparison of the ρ0 cross sections with other leptoproduction experiments is presented. The ω results represent the first observation of this inclusive channel in high energy leptoproduction. The ρ0 and ω yields are found to be equal as may be expected from the available density of states in isospin space. This contrasts with spin angular momentum where the vector to pseudoscalar meson ratio is suppressed relative to the available number of spin states.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Charm Production in Deep Inelastic Muon - Iron Interactions at 200-{GeV}/$c$

The European Muon collaboration Arneodo, M. ; Aubert, J.J. ; Bassompierre, G. ; et al.
Z.Phys.C 35 (1987) 1, 1987.
Inspire Record 230629 DOI 10.17182/hepdata.15765

Dimuon and trimuon events have been studied in deep inelastic muon scattering on an iron target at an incident muon energy of 200 GeV. The events are shown to originate mainly from charm production. Comparison of the measured cross sections with data taken at higher muon energies shows that charm production originates predominantly from transverse virtual photons. Within the framework of the photon gluon fusion model this indicates that the parity of the gluon is odd.

1 data table
Table 1

No description provided.


PRODUCTION OF BACKWARD PROTONS IN LAB SYSTEM WITH 0.2-GeV/c - 0.5-GeV/c MOMENTA IN anti-p A INTERACTIONS AT 40-GeV/c

Gabunia, L.L. ; Dzhavrishvili, A.K. ; Ivanova, A.B. ; et al.
Yad.Fiz. 46 (1987) 540-548, 1987.
Inspire Record 236228 DOI 10.17182/hepdata.39002

None

14 data tables
Table 1

NUCLEUS IS C6J.

Table 2

NUCLEUS IS C6J.

Table 3

NUCLEUS IS C6J.

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INVESTIGATION OF p C INTERACTION AT P(p) = 10-GeV/c WITH THE EMISSION OF CUMULATIVE NEUTRAL PIONS

Armutliisky, D. ; Bogdanovich, E. ; Gasparian, A.P. ; et al.
JINR-P1-86-459, 1986.
Inspire Record 235075 DOI 10.17182/hepdata.39018

None

12 data tables
Table 1

No description provided.

Table 2

ALL NEGATIVE PARTICLES WAS CONSIDERED AS PI-.

Table 3

ALL NEGATIVE PARTICLES WAS CONSIDERED AS PI-.

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COMPARISON OF THE PARTICLE FLOW IN q anti-q g AND q anti-q gamma EVENTS IN e+ e- ANNIHILATION

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 945, 1986.
Inspire Record 230224 DOI 10.17182/hepdata.38183

We compare the particle flow in the event plane of three-jet qq¯g (quark-antiquark-gluon) events with the particle flow in radiative annihilation events qq¯γ (quark-antiquark-photon) for similar kinematic configurations. In the angular region between quark and antiquark jet, we find a significant decrease in particle density for qq¯g as compared to qq¯γ. This effect is predicted in QCD as a result of destructive interference between soft-gluon radiation from quark, antiquark, and hard gluon.

2 data tables
Table 1

No description provided.

Table 2

No description provided.